Let's leave both - this can cover people looking for 10.6 -> 10.8 and the other for 10.6 -> 10.7 upgrades. It's not logical to expect someone to know to ask about the previous version of the OS or when a change happened.
– bmike♦Aug 16 '12 at 14:53

4 Answers
4

This change actually happened from Snow Leopard to Lion with the introduction of Natural Scrolling to match iOS scrolling behavior where the motion is expected to work on the content - not the scroll indicator - as the two move in opposite directions.

The system preference for scroll direction is all-or-nothing and applies to every input device uniformly. With some things, this just doesn't make sense. If you want fine-grained control of which input devices scroll in which way (for example, if you want touchpads to use the "natural" scrolling while having the scroll wheel use traditional scrolling), try ScrollReverser.

Unf. for me, treats the Magic Mouse and conventional scrollwheel mouse both as "mouse"; had hoped I could set things up device by device. Otherwise a very nice find (+1, etc).
– ruffinJan 25 '14 at 15:13

You need to go to System Preferences icon on the Dock, then mouse in Hardware category, then scroll direction. The description could be different because I have it in Spanish that I am translating, but you need to un-check it anyway, it worked for me.

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